Batch type production formats are known that generate hypochlorous acid-bearing acidic electrolyzed water, using raw water that has been stored in a vessel having a fixed capacity. These formats use an electrolysis tank in which the positive electrode chamber and the negative electrode chamber have been divided by a separation membrane. The electrolysis is done in the positive electrode chamber and the negative electrode chamber, using water for electrolytic processing that has had a small amount of a chloride-containing salt added to it to form the electrolyte. Typically, flow through an anode compartment generates acid electrolyzed water, and flow through a cathode compartment generates alkaline electrolyzed water.
However, there are many problems with this approach. In particular, although acidic electrolyzed water possesses strong bactericidal power, and is a desirable water that causes little contamination of people or the environment, the production systems of the past have weaknesses such as the fact that the resulting acidic water contains salt, has a strong smell of chlorine, and easily corrodes metals. In addition, from the standpoint of the production process, there are troublesome cases in which the generation of alkaline water creates problems. In the marketplace, devices that generate salt-free acidic electrolyzed water without generating alkaline water are not readily available. Finally, in some production systems that employ a cation exchange membrane, the presence of some cations in the salt can foul the ion-selective membrane. Consequently, restrictions are placed on the purity of the electrolyte salt that limit the possible grades of salt that can be used in such systems.
A system is desired with which stable, reproducible generation of acidic electrolyzed water can be done, where the generation of alkaline water can be avoided or minimized, and where limits on the impurity content of the electrolyte salt can be relaxed.